Climate change

Climate change: degree of sea level rise now inevitable, study finds

A new document shows that the melting of Greenland’s ice alone will cause an inevitable rise in sea level of around a quarter of a meter. Photo / 123rf

By Hamish Cardwell of RNZ

A worrying new study shows that a sea level rise of around 25cm is now inevitable – even if all climate-damaging actions cease immediately.

The paper, published in the journal Nature Climate Change, showed that melting Greenland ice alone would cause the rise.

And a separate OECD study showed member countries were pushing consumption patterns in the wrong direction, with a huge increase in fossil fuel subsidies last year.

“There is no bigger problem”

Previous studies of ice sheets have relied on computers to model thaw – which has produced widely varying results.

The new paper, on the other hand, also used satellite measurements from the past two decades.

It further showed that if emissions continued, a sea level rise of more than one meter was likely.

The study did not specify a timeline.

Many parts of New Zealand are vulnerable to rising seas.

There would be severe consequences for whole swaths of the Auckland and Wellington foreshore with elevation as low as 10cm.

Professor James Renwick, a climatologist at the University of Victoria, said action to reduce the use of fossil fuels could not be more urgent.

“We need to reduce emissions immediately, we need to achieve a 50% reduction globally this decade if we are to avoid these kinds of impacts on the track.

“There’s no bigger problem to deal with, it amazes me that governments are still kind of talking about ‘getting ready to do something’ when we’re facing absolutely catastrophic impacts.”

Renwick said he was at a science conference today on Antarctica and said the continent’s contribution to sea level rise is expected to be far greater than Greenland’s.

“There is a threshold at about two degrees of warming where we definitely commit at least the West Antarctic ice sheet to irreversible melting, which would add three or four meters to sea level rise.”

The planet has warmed by an average of about 1.1°C since 1850.

Countries have embarked on efforts that, if acted upon, would continue to warm around 1.9 to 2.4°C.

But even the lowest of these numbers is well above the 1.5°C mark above which scientists say there will be devastating consequences across the globe.

OECD report shows its members’ fossil fuel subsidies are skyrocketing

One of the few truly effective ways to drastically reduce emissions is to stop burning fossil fuels.

But a new report from the OECD shows that government subsidies and support for the production and consumption of fossil fuels have doubled in the past year to nearly US$700 billion ($1.1 trillion) per year. compared to 2020.

Energy prices rose as the global economy rebounded.

The Russian invasion of Ukraine is expected to lead to further grant increases this year.

Renwick said the global economy was still powered by fossil fuels, so the transition had to be managed, but the change needed much more urgency.

“Because if we don’t, the other side of the coin is [that] the instability caused by climate change will destroy everything anyway.

“We are in a really dangerous situation here, we need action as soon as possible.”

He said the devastating floods in Pakistan right now were just one example of the kind of future devastation that global warming would make increasingly common.